Mobile and fixed data transmission and data services are constantly making progress, wherein such services provide various communication services, such as voice, video, packet data, messaging, broadcast, etc. In recent years, LTE and LTE-A have been specified, which use the Evolved Universal Terrestrial Radio Access Network (E-UTRAN) as radio communication architecture according to 3GPP specifications.
Furthermore, network virtualization is used in recent technologies, which splits conventional networks and their network elements into subsets to be used, operated and managed by different organizationally independent organizations. The use of network virtualization offers flexibility in the development of future network architectures.
In the context of network virtualization, the migration of network elements in combination with software defined networking (SDN) is capable of transforming today's networks into a fully software-defined infrastructure that is both highly efficient and flexible. Similarly, a fully software-defined infrastructure can also be achieved by the migration of network elements in combination with network functions virtualisation (NFV). Accordingly, a software defined networking (SDN) architecture and/or a network functions virtualisation (NFV) architecture is about to be adopted in mobile and/or fixed communication systems.
Within the development of software-defined infrastructures for/in networking, a separation of the control plane and the data plane (which may equally be referred to as user plane, forwarding plane, etc.) is employed. The communication between the separated control and data planes is accomplished via dedicated communication protocols, such as e.g. Open Flow, ForCES (Forwarding and Control Element Separation protocol), or the like. To this end, an intermediate controller is typically implemented as an inter-plane communication interface, which is configured to control the respective entities on the control plane and the data plane in accordance with the applicable communication protocol, such as e.g. OpenFlow, ForCES (Forwarding and Control Element Separation protocol), or the like.
Referring to 3GPP specifications, network elements such as eNB, RNC, SGSN, GGSN, SGW, PGW, ePDG, BRAS, and TWAN, as well as LSR, may be implemented in a SDN and/or NFV architecture, thus being (logically) decomposed in a control plane entity and a data plane entity with an intermediate inter-plane communication controller (which may be integrated in/with the control plane entity).
However, in SDN and/or NFV architectures, the control plane entity (of any one of such network elements) is typically not able to appropriately handle a signaling message on the data plane, i.e. to generate and send a corresponding outgoing message on the data plane to such incoming signaling message on the data plane.
For example, the GPRS Tunneling Protocol (GTP) defines a user plane protocol part (GTP-U) (in 3GPP TS 29.281), wherein signaling messages are sent via a (GTP-U) tunnel between network elements (also referred to as GTP-U peers) for path management and tunnel management. One of such GTP-U signaling messages is a GTP-U Echo Request, with which a GTP-U peer tries to find out whether the GTP-U peer at the opposite tunnel endpoint is alive, and which has thus to be properly responded by the GTP-U peer at the opposite tunnel endpoint by a GTP-U Echo Response so as to facilitate an appropriate path/tunnel management. However, if a network elements representing a GTP-U tunnel endpoint, i.e. a GTP-U peer, is implemented in a SDN architecture with decomposed control and user plane entities, it is not feasible to respond to respond to the GTP-U Echo Request on the user plane, i.e. to generate and send a GTP-U Echo Response on the user plane.
Thus, there is a need to enable handling of signaling messages on the data plane in a software-defined architecture.